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91.
Despite their unmatched popularity in many research areas, microsatellites have not yet become a major tool for the inference of genealogical relationships of closely related species. Recent studies have successfully extended the repertoire of microsatellite analysis beyond population genetics and demonstrate that phylogenetic relationships of closely related species can be inferred accurately with fewer loci than previously assumed.  相似文献   
92.
Chlorocatechol 1,2-dioxygenase (CC 1,2-DO), chloromuconate cycloisomerase (CMCI), chloromuconolactone isomerase (CMLI), and dienolactone hydrolase (DELH), the key enzymes of a new modified ortho-pathway in Rhodococcus opacus 1CP cells utilizing 2-chlorophenol via a 3-chlorocatechol branch of a modified ortho-pathway, were isolated and characterized. CC 1,2-DO showed the maximum activity with 3-chlorocatechol; its activity with catechol and 4-chlorocatechol was 93 and 50%, respectively. The enzyme of the studied pathway had physicochemical properties intermediate between the pyrocatechase of ordinary and chlorocatechase of modified pathways described earlier for this strain. In contrast to the enzymes investigated earlier, CMCI of the new pathway exhibited high substrate specificity. The enzyme had K m for 2-chloromuconate of 142.86 M, V max = 71.43 U/mg, pH optimum around 6.0, and temperature optimum at 65°C. CMCI converted 2-chloromuconate into 5-chloromuconolactone. CMLI converted 5-chloromuconolactone into cis-dienolactone used as a substrate by DELH; this enzyme did not convert trans-dienolactone. DELH had Km for cis-dienolactone of 200 M, V max = 167 U/mg, pH optimum of 8.6, and temperature optimum of 40°C. These results confirm the existence of a new modified ortho-pathway for utilization of 2-chlorophenol by R. opacus 1CP.  相似文献   
93.
Life expectancy, especially in the older age groups, is growing enormously due to better social and medical care. According to published data on disabled people (1997), about 30 % of the total population (7,119,000) in Austria suffer from at least one physical disability. In this study, data from a micro census as well as a report from the Federal Ministry for Social Security and Generations is analyzed to illuminate the situation of impaired people with a focus on the capital Vienna. Among other results, it is anticipated that a large number of disabled people receive no help at all. About every 7th person regularly receives care, every 10th receives daily support. Care intensity increases with age showing a clear progression from the age of 60 onwards. 88% of the main supporting individuals are related to the handicapped person being supported. Women generally exhibit a much higher participation in nursing. The socio-political developments are discussed.  相似文献   
94.
Until now, the predominant use cases of industrial robots have been routine handling tasks in the automotive industry. In biotechnology and tissue engineering, in contrast, only very few tasks have been automated with robots. New developments in robot platform and robot sensor technology, however, make it possible to automate plants that largely depend on human interaction with the production process, e.g., for material and cell culture fluid handling, transportation, operation of equipment, and maintenance. In this paper we present a robot system that lends itself to automating routine tasks in biotechnology but also has the potential to automate other production facilities that are similar in process structure. After motivating the design goals, we describe the system and its operation, illustrate sample runs, and give an assessment of the advantages. We conclude this paper by giving an outlook on possible further developments.  相似文献   
95.
Yeast reporter system for rapid determination of estrogenic activity   总被引:5,自引:0,他引:5  
An in vitro test system for the determination of estrogens, xeno- and phytoestrogens, based on the activation of human estrogen receptor-alpha, has been examined for ability in monitoring environmental estrogens. The system consists of an expression plasmid for the human estrogen receptor-alpha and a reporter plasmid containing the lacZ gene under the control of the vitellogenin hormone response element. These plasmids have been transformed into S. cerevisae. Cultivation of yeast in the presence of estrogenic substances leads to activation of the estrogen receptor and induces the expression of the reporter lacZ. beta-Galactosidase activity of the translated gene lacZ is a measure of the estrogenic activity of a compound. First, the selectivity of the system was compared to data available in the literature. Then the sensitivity of the system was checked. The detection limit is 0.1 ng 17-beta estradiol or an equivalent activity per liter, if a sample can be concentrated 1000-fold. The system has been further characterized by selected compounds with known and unknown estrogenic activity.  相似文献   
96.
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98.
The triterpenoid aldehydes, gossypol (1), 6-methoxygossypol (2) and 6,6′-dimethoxygossypol (3); and the sesquiterpenoid aldehydes, hemigossypol (4) and methoxyhemigossypol (5), were isolated from 1-week-old roots of Gossypium hirsutum and G. barbadense and identified. This is the first report of 2 and 3 in nature and of 4 and 5 from healthy roots. Compounds 2 and 3 also constituted 30% of the total terpenoid aldehydes in the seeds of 1 cultivar of G. barbadense, but occurred only in trace quantities in those of G. hirsutum. Spectral data (UV, IR, NMR, MS) and proof of structure for 2 and 3 are presented.  相似文献   
99.
We evaluated the status of native ladybird assemblages in the presence of the non-native ladybird Harmonia axyridis Pallas (Coleoptera: Coccinellidae) in three European countries. To achieve this, we assessed the abundance of ladybirds from common host plants in urban areas of Great Britain, Czech Republic and Slovak Republic in 2014. We determined (i) the effects of season, host plant, location, abundance of H. axyridis and aphids on the ladybird species assemblage, (ii) the relationship between ladybird abundance and aphid density, (iii) the relationship between diversity of native ladybird species and the abundance of H. axyridis. There was a non-linear relationship between abundance of ladybirds and abundance of aphids but we found the abundance of other ladybird species was not correlated with H. axyridis. We highlight the value of large-spatial scale studies for revealing patterns in community assemblages and ultimately informing understanding of ecosystem resilience.  相似文献   
100.
In plant post-embryonic epidermis mitogen-activated protein kinase (MAPK) signaling promotes differentiation of pavement cells and inhibits initiation of stomata. Stomata are cells specialized to modulate gas exchange and water loss. Arabidopsis MAPKs MPK3 and MPK6 are at the core of the signaling cascade; however, it is not well understood how the activity of these pleiotropic MAPKs is constrained spatially so that pavement cell differentiation is promoted only outside the stomata lineage. Here we identified a PP2C-type phosphatase termed AP2C3 (Arabidopsis protein phosphatase 2C) that is expressed distinctively during stomata development as well as interacts and inactivates MPK3, MPK4 and MPK6. AP2C3 co-localizes with MAPKs within the nucleus and this localization depends on its N-terminal extension. We show that other closely related phosphatases AP2C2 and AP2C4 are also MAPK phosphatases acting on MPK6, but have a distinct expression pattern from AP2C3. In accordance with this, only AP2C3 ectopic expression is able to stimulate cell proliferation leading to excess stomata development. This function of AP2C3 relies on the domains required for MAPK docking and intracellular localization. Concomitantly, the constitutive and inducible AP2C3 expression deregulates E2F-RB pathway, promotes the abundance and activity of CDKA, as well as changes of CDKB1;1 forms. We suggest that AP2C3 downregulates the MAPK signaling activity to help maintain the balance between differentiation of stomata and pavement cells.  相似文献   
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